Under AT&T’s offer, which starts today, those trading in a smartphone who switch to AT&T can get up to $250 in credit, with those willing to sign up for one of AT&T’s Next plans able to get an additional $200 credit.

Of course, while AT&T can beat T-Mobile to the punch time-wise, AT&T has a lot more customers to steal than does its smaller rival. Plus, T-Mobile’s plans are generally less expensive than AT&T’s.